The thought translation device : a neurophysiological approach to communication in total motor paralysis

• Published in: Experimental brain research Vol. 124; no. 2; pp. 223 - 232
• Main Authors: KÜBLER, A, KOTCHOUBEY, B, HINTERBERGER, T, GHANAYIM, N, PERELMOUTER, J, SCHAUER, M, FRITSCH, C, TAUB, E, BIRBAUMER, N
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01.01.1999
• Subjects: Adult; Amyotrophic Lateral Sclerosis - rehabilitation; Biofeedback, Psychology - physiology; Biological and medical sciences; Cerebral Cortex - physiology; Communication Aids for Disabled; Communication Barriers; Computer User Training; Diseases of the nervous system; Electroencephalography; Electrooculography; Female; Humans; Male; Medical sciences; Middle Aged; Polyneuropathies - rehabilitation; Quadriplegia - rehabilitation; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); User-Computer Interface; Human; Tetraplegia; Nervous system diseases; Instrumental conditioning; Slow potential; Amyotrophic lateral sclerosis; Electroencephalography; Genetic disease; Acquisition process; Treatment; Central nervous system disease; Self control; Degenerative disease; Paralysis; Spinal cord disease; Computer aid; Communication
• ISSN: 0014-4819; 1432-1106
• DOI: 10.1007/s002210050617

A thought translation device (TTD) for brain-computer communication is described. Three patients diagnosed with amyotrophic lateral sclerosis (ALS), with total motor paralysis, were trained for several months. In order to enable such patients to communicate without any motor activity, a technique was developed where subjects learn to control their slow cortical potentials (SCP) in a 2-s rhythm, producing either cortical negativity or positivity according to the task requirement. SCP differences between a baseline interval and an active control interval are transformed into vertical or horizontal cursor movements on a computer screen. Learning SCP self regulation followed an operant-conditioning paradigm with individualized shaping procedures. After prolonged training over more than 100 sessions, all patients achieved self-control, leading to a 70-80% accuracy for two patients. The learned cortical skill enabled the patients to select letters or words in a language-supporting program (LSP) developed for inter-personal communication. The results demonstrate that the fast and stable SCP self-control can be achieved with operant training and without mediation of any muscle activity. The acquired skill allows communication even in total locked-in states.